[PATCH v2 2/2] mtd: spi-nor: add rockchip serial flash controller driver
Shawn Lin
shawn.lin at rock-chips.com
Thu Nov 17 18:59:05 PST 2016
Add rockchip serial flash controller driver
Signed-off-by: Shawn Lin <shawn.lin at rock-chips.com>
---
Changes in v2:
- fix typos
- add some comment for buffer and others operations
- rename SFC_MAX_CHIP_NUM to MAX_CHIPSELECT_NUM
- use u8 for cs
- return -EINVAL for default case of get_if_type
- use readl_poll_*() to check timeout cases
- simplify and clarify some condition checks
- rework the bitshifts to simplify the code
- define SFC_CMD_DUMMY(x)
- fix ummap for dma read path and finish all the
cache maintenance.
- rename to rockchip_sfc_chip_priv and embed struct spi_nor
in it.
- add MODULE_AUTHOR
- add runtime PM and general PM support.
- Thanks for Marek's comments. Link:
http://lists.infradead.org/pipermail/linux-mtd/2016-November/070321.html
MAINTAINERS | 8 +
drivers/mtd/spi-nor/Kconfig | 7 +
drivers/mtd/spi-nor/Makefile | 1 +
drivers/mtd/spi-nor/rockchip-sfc.c | 971 +++++++++++++++++++++++++++++++++++++
4 files changed, 987 insertions(+)
create mode 100644 drivers/mtd/spi-nor/rockchip-sfc.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 1cd38a7..eb7e06d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10266,6 +10266,14 @@ L: linux-serial at vger.kernel.org
S: Odd Fixes
F: drivers/tty/serial/rp2.*
+ROCKCHIP SERIAL FLASH CONTROLLER DRIVER
+M: Shawn Lin <shawn.lin at rock-chips.com>
+L: linux-mtd at lists.infradead.org
+L: linux-rockchip at lists.infradead.org
+S: Maintained
+F: Documentation/devicetree/bindings/mtd/rockchip-sfc.txt
+F: drivers/mtd/spi-nor/rockchip-sfc.c
+
ROSE NETWORK LAYER
M: Ralf Baechle <ralf at linux-mips.org>
L: linux-hams at vger.kernel.org
diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
index 4a682ee..bf783a8 100644
--- a/drivers/mtd/spi-nor/Kconfig
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -76,4 +76,11 @@ config SPI_NXP_SPIFI
Flash. Enable this option if you have a device with a SPIFI
controller and want to access the Flash as a mtd device.
+config SPI_ROCKCHIP_SFC
+ tristate "Rockchip Serial Flash Controller(SFC)"
+ depends on ARCH_ROCKCHIP || COMPILE_TEST
+ depends on HAS_IOMEM && HAS_DMA
+ help
+ This enables support for rockchip serial flash controller.
+
endif # MTD_SPI_NOR
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index 121695e..364d4c6 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o
obj-$(CONFIG_SPI_HISI_SFC) += hisi-sfc.o
obj-$(CONFIG_MTD_MT81xx_NOR) += mtk-quadspi.o
obj-$(CONFIG_SPI_NXP_SPIFI) += nxp-spifi.o
+obj-$(CONFIG_SPI_ROCKCHIP_SFC) += rockchip-sfc.o
diff --git a/drivers/mtd/spi-nor/rockchip-sfc.c b/drivers/mtd/spi-nor/rockchip-sfc.c
new file mode 100644
index 0000000..061f2c4
--- /dev/null
+++ b/drivers/mtd/spi-nor/rockchip-sfc.c
@@ -0,0 +1,971 @@
+/*
+ * Rockchip Serial Flash Controller Driver
+ *
+ * Copyright (c) 2016, Rockchip Inc.
+ * Author: Shawn Lin <shawn.lin at rock-chips.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/spi-nor.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+/* System control */
+#define SFC_CTRL 0x0
+#define SFC_CTRL_COMMON_BITS_1 0x0
+#define SFC_CTRL_COMMON_BITS_2 0x1
+#define SFC_CTRL_COMMON_BITS_4 0x2
+#define SFC_CTRL_DATA_BITS_SHIFT 12
+#define SFC_CTRL_DATA_BITS_MASK 0x3
+#define SFC_CTRL_ADDR_BITS_SHIFT 10
+#define SFC_CTRL_ADDR_BITS_MASK 0x3
+#define SFC_CTRL_CMD_BITS_SHIFT 8
+#define SFC_CTRL_CMD_BITS_MASK 0x3
+#define SFC_CTRL_PHASE_SEL_NEGETIVE BIT(1)
+
+/* Interrupt mask */
+#define SFC_IMR 0x4
+#define SFC_IMR_RX_FULL BIT(0)
+#define SFC_IMR_RX_UFLOW BIT(1)
+#define SFC_IMR_TX_OFLOW BIT(2)
+#define SFC_IMR_TX_EMPTY BIT(3)
+#define SFC_IMR_TRAN_FINISH BIT(4)
+#define SFC_IMR_BUS_ERR BIT(5)
+#define SFC_IMR_NSPI_ERR BIT(6)
+#define SFC_IMR_DMA BIT(7)
+/* Interrupt clear */
+#define SFC_ICLR 0x8
+#define SFC_ICLR_RX_FULL BIT(0)
+#define SFC_ICLR_RX_UFLOW BIT(1)
+#define SFC_ICLR_TX_OFLOW BIT(2)
+#define SFC_ICLR_TX_EMPTY BIT(3)
+#define SFC_ICLR_TRAN_FINISH BIT(4)
+#define SFC_ICLR_BUS_ERR BIT(5)
+#define SFC_ICLR_NSPI_ERR BIT(6)
+#define SFC_ICLR_DMA BIT(7)
+/* FIFO threshold level */
+#define SFC_FTLR 0xc
+#define SFC_FTLR_TX_SHIFT 0
+#define SFC_FTLR_TX_MASK 0x1f
+#define SFC_FTLR_RX_SHIFT 8
+#define SFC_FTLR_RX_MASK 0x1f
+/* Reset FSM and FIFO */
+#define SFC_RCVR 0x10
+#define SFC_RCVR_RESET BIT(0)
+/* Enhanced mode */
+#define SFC_AX 0x14
+/* Address Bit number */
+#define SFC_ABIT 0x18
+/* Interrupt status */
+#define SFC_ISR 0x1c
+#define SFC_ISR_COMMON_ACTIVE 0x1
+#define SFC_ISR_COMMON_MASK 0x1
+#define SFC_ISR_RX_FULL_SHIFT 0
+#define SFC_ISR_RX_UFLOW_SHIFT 1
+#define SFC_ISR_TX_OFLOW_SHIFT 2
+#define SFC_ISR_TX_EMPTY_SHIFT 3
+#define SFC_ISR_TX_FINISH_SHIFT 4
+#define SFC_ISR_BUS_ERR_SHIFT 5
+#define SFC_ISR_NSPI_ERR_SHIFT 6
+#define SFC_ISR_DMA_SHIFT 7
+/* FIFO status */
+#define SFC_FSR 0x20
+#define SFC_FSR_TX_IS_FULL BIT(0)
+#define SFC_FSR_TX_IS_EMPTY BIT(1)
+#define SFC_FSR_RX_IS_EMPTY BIT(2)
+#define SFC_FSR_RX_IS_FULL BIT(3)
+#define SFC_FSR_TX_WATER_LVL_SHIFT 8
+#define SFC_FSR_TX_WATER_LVL_MASK 0x1f
+#define SFC_FSR_RX_WATER_LVL_SHIFT 16
+#define SFC_FSR_RX_WATER_LVL_MASK 0x1f
+/* FSM status */
+#define SFC_SR 0x24
+#define SFC_SR_IS_IDLE 0x0
+#define SFC_SR_IS_BUSY 0x1
+/* Raw interrupt status */
+#define SFC_RISR 0x28
+#define SFC_RISR_RX_FULL BIT(0)
+#define SFC_RISR_RX_UNDERFLOW BIT(1)
+#define SFC_RISR_TX_OVERFLOW BIT(2)
+#define SFC_RISR_TX_EMPTY BIT(3)
+#define SFC_RISR_TRAN_FINISH BIT(4)
+#define SFC_RISR_BUS_ERR BIT(5)
+#define SFC_RISR_NSPI_ERR BIT(6)
+#define SFC_RISR_DMA BIT(7)
+/* Master trigger */
+#define SFC_DMA_TRIGGER 0x80
+/* Src or Dst addr for master */
+#define SFC_DMA_ADDR 0x84
+/* Command */
+#define SFC_CMD 0x100
+#define SFC_CMD_IDX_SHIFT 0
+#define SFC_CMD_IDX_MASK 0xff
+#define SFC_CMD_DUMMY_SHIFT 8
+#define SFC_CMD_DUMMY_MASK 0xf
+#define SFC_CMD_DIR_RD 0
+#define SFC_CMD_DIR_WR 1
+#define SFC_CMD_DIR_SHIFT 12
+#define SFC_CMD_DIR_MASK 0x1
+#define SFC_CMD_ADDR_ZERO (0x0 << 14)
+#define SFC_CMD_ADDR_24BITS (0x1 << 14)
+#define SFC_CMD_ADDR_32BITS (0x2 << 14)
+#define SFC_CMD_ADDR_FRS (0x3 << 14)
+#define SFC_CMD_TRAN_BYTES_SHIFT 16
+#define SFC_CMD_TRAN_BYTES_MASK 0x3fff
+#define SFC_CMD_CS_SHIFT 30
+#define SFC_CMD_CS_MASK 0x3
+/* Address */
+#define SFC_ADDR 0x104
+/* Data */
+#define SFC_DATA 0x108
+
+#define SFC_MAX_CHIPSELECT_NUM 4
+#define SFC_MAX_IDLE_RETRY 10000
+#define SFC_WAIT_IDLE_TIMEOUT 1000000
+#define SFC_DMA_MAX_LEN 0x4000
+#define SFC_DMA_MAX_MASK (SFC_DMA_MAX_LEN - 1)
+#define SFC_CMD_DUMMY(x) \
+ (((x) & SFC_CMD_DUMMY_MASK) << SFC_CMD_DUMMY_SHIFT)
+
+enum rockchip_sfc_iftype {
+ IF_TYPE_STD,
+ IF_TYPE_DUAL,
+ IF_TYPE_QUAD,
+};
+
+struct rockchip_sfc;
+struct rockchip_sfc_chip_priv {
+ u8 cs;
+ u32 clk_rate;
+ struct spi_nor nor;
+ struct rockchip_sfc *sfc;
+};
+
+struct rockchip_sfc {
+ struct device *dev;
+ struct mutex lock;
+ void __iomem *regbase;
+ struct clk *hclk;
+ struct clk *clk;
+ /* virtual mapped addr for dma_buffer */
+ void *buffer;
+ dma_addr_t dma_buffer;
+ struct completion cp;
+ struct rockchip_sfc_chip_priv flash[SFC_MAX_CHIPSELECT_NUM];
+ u32 num_chip;
+ bool use_dma;
+ /* use negative edge of hclk to latch data */
+ bool negative_edge;
+};
+
+static int get_if_type(enum read_mode flash_read)
+{
+ enum rockchip_sfc_iftype if_type;
+
+ switch (flash_read) {
+ case SPI_NOR_DUAL:
+ if_type = IF_TYPE_DUAL;
+ break;
+ case SPI_NOR_QUAD:
+ if_type = IF_TYPE_QUAD;
+ break;
+ case SPI_NOR_NORMAL:
+ case SPI_NOR_FAST:
+ if_type = IF_TYPE_STD;
+ break;
+ default:
+ pr_err("unsupported SPI read mode\n");
+ return -EINVAL;
+ }
+
+ return if_type;
+}
+
+static int rockchip_sfc_reset(struct rockchip_sfc *sfc)
+{
+ int err;
+ u32 status;
+
+ writel_relaxed(SFC_RCVR_RESET, sfc->regbase + SFC_RCVR);
+
+ err = readl_poll_timeout(sfc->regbase + SFC_RCVR, status,
+ !(status & SFC_RCVR_RESET), 20,
+ jiffies_to_usecs(HZ));
+ if (err)
+ dev_err(sfc->dev, "SFC reset never finished\n");
+
+ /* Still need to clear the masked interrupt from RISR */
+ writel_relaxed(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
+ SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
+ SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
+ SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
+ sfc->regbase + SFC_ICLR);
+ return err;
+}
+
+static int rockchip_sfc_init(struct rockchip_sfc *sfc)
+{
+ int err;
+
+ err = rockchip_sfc_reset(sfc);
+ if (err)
+ return err;
+
+ /* Mask all eight interrupts */
+ writel_relaxed(0xff, sfc->regbase + SFC_IMR);
+
+ /*
+ * Phase configure for sfc to latch data by using
+ * ahb clock, and this configuration should be Soc
+ * specific.
+ */
+ if (sfc->negative_edge)
+ writel_relaxed(SFC_CTRL_PHASE_SEL_NEGETIVE,
+ sfc->regbase + SFC_CTRL);
+ else
+ writel_relaxed(0, sfc->regbase + SFC_CTRL);
+
+ return 0;
+}
+
+static int rockchip_sfc_prep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ int ret;
+
+ mutex_lock(&sfc->lock);
+ pm_runtime_get_sync(sfc->dev);
+
+ ret = clk_set_rate(sfc->clk, priv->clk_rate);
+ if (ret)
+ goto out;
+
+ ret = clk_prepare_enable(sfc->clk);
+ if (ret)
+ goto out;
+
+ return 0;
+
+out:
+ mutex_unlock(&sfc->lock);
+ return ret;
+}
+
+static void rockchip_sfc_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+
+ clk_disable_unprepare(sfc->clk);
+ mutex_unlock(&sfc->lock);
+ pm_runtime_mark_last_busy(sfc->dev);
+ pm_runtime_put_autosuspend(sfc->dev);
+}
+
+static int rockchip_sfc_wait_op_finish(struct rockchip_sfc *sfc)
+{
+ int err;
+ u32 status;
+
+ /*
+ * Note: tx and rx share the same fifo, so the rx's water level
+ * is the same as rx's, which means this function could be reused
+ * for checking the read operations as well.
+ */
+ err = readl_poll_timeout(sfc->regbase + SFC_FSR, status,
+ status & SFC_FSR_TX_IS_EMPTY,
+ 20, jiffies_to_usecs(2 * HZ));
+ if (err)
+ dev_err(sfc->dev, "SFC tx never empty\n");
+
+ return err;
+}
+
+static int rockchip_sfc_op_reg(struct spi_nor *nor,
+ u8 opcode, int len, u8 optype)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ u32 reg;
+ bool tx_no_empty, rx_no_empty, is_busy;
+
+ reg = readl_relaxed(sfc->regbase + SFC_FSR);
+ tx_no_empty = !(reg & SFC_FSR_TX_IS_EMPTY);
+ rx_no_empty = !(reg & SFC_FSR_RX_IS_EMPTY);
+
+ is_busy = readl_relaxed(sfc->regbase + SFC_SR);
+
+ if (tx_no_empty || rx_no_empty || is_busy)
+ rockchip_sfc_reset(sfc);
+
+ reg = (opcode & SFC_CMD_IDX_MASK) << SFC_CMD_IDX_SHIFT;
+ reg |= (len & SFC_CMD_TRAN_BYTES_MASK) << SFC_CMD_TRAN_BYTES_SHIFT;
+ reg |= (priv->cs & SFC_CMD_CS_MASK) << SFC_CMD_CS_SHIFT;
+ reg |= (optype & SFC_CMD_DIR_MASK) << SFC_CMD_DIR_SHIFT;
+
+ writel_relaxed(reg, sfc->regbase + SFC_CMD);
+
+ return rockchip_sfc_wait_op_finish(sfc);
+}
+
+static int rockchip_sfc_read_reg(struct spi_nor *nor, u8 opcode,
+ u8 *buf, int len)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ int ret;
+ u32 tmp, i;
+
+ ret = rockchip_sfc_op_reg(nor, opcode, len, SFC_CMD_DIR_RD);
+ if (ret)
+ return ret;
+
+ while (len > 0) {
+ tmp = readl_relaxed(sfc->regbase + SFC_DATA);
+ for (i = 0; i < ((len > 4) ? 4 : len); i++)
+ *buf++ = (u8)((tmp >> (i * 8)) & 0xff);
+
+ len = len - 4;
+ }
+
+ return 0;
+}
+
+static int rockchip_sfc_write_reg(struct spi_nor *nor, u8 opcode,
+ u8 *buf, int len)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ u32 dwords, i;
+
+ /* Align bytes to dwords */
+ dwords = (len + 3) >> 2;
+
+ for (i = 0; i < dwords; i++)
+ writel_relaxed(*(buf + 4 * i), sfc->regbase + SFC_DATA);
+
+ return rockchip_sfc_op_reg(nor, opcode, len, SFC_CMD_DIR_WR);
+}
+
+static inline void rockchip_sfc_setup_transfer(struct spi_nor *nor,
+ loff_t from_to,
+ size_t len, u8 op_type)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ u32 reg;
+ u8 if_type = 0;
+
+ if (op_type == SFC_CMD_DIR_WR)
+ reg = (nor->program_opcode & SFC_CMD_IDX_MASK) <<
+ SFC_CMD_IDX_SHIFT;
+ else
+ reg = (nor->read_opcode & SFC_CMD_IDX_MASK) <<
+ SFC_CMD_IDX_SHIFT;
+
+ reg |= op_type << SFC_CMD_DIR_SHIFT;
+ reg |= (nor->addr_width == 4) ?
+ SFC_CMD_ADDR_32BITS : SFC_CMD_ADDR_24BITS;
+
+ if_type = get_if_type(nor->flash_read);
+ writel_relaxed((if_type << SFC_CTRL_DATA_BITS_SHIFT) |
+ (if_type << SFC_CTRL_ADDR_BITS_SHIFT) |
+ (if_type << SFC_CTRL_CMD_BITS_SHIFT) |
+ (sfc->negative_edge ? SFC_CTRL_PHASE_SEL_NEGETIVE : 0),
+ sfc->regbase + SFC_CTRL);
+
+ reg |= (priv->cs & SFC_CMD_CS_MASK) << SFC_CMD_CS_SHIFT;
+ reg |= (len & SFC_CMD_TRAN_BYTES_MASK) << SFC_CMD_TRAN_BYTES_SHIFT;
+
+ if (op_type == SFC_CMD_DIR_RD)
+ reg |= SFC_CMD_DUMMY(nor->read_dummy);
+
+ /* Should minus one as 0x0 means 1 bit flash address */
+ writel_relaxed(nor->addr_width * 8 - 1, sfc->regbase + SFC_ABIT);
+ writel_relaxed(reg, sfc->regbase + SFC_CMD);
+ writel_relaxed(from_to, sfc->regbase + SFC_ADDR);
+}
+
+static int rockchip_sfc_dma_transfer(struct spi_nor *nor, loff_t from_to,
+ dma_addr_t dma_buf, size_t len, u8 op_type)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ u32 reg;
+ int err = 0;
+
+ init_completion(&sfc->cp);
+
+ writel_relaxed(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
+ SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
+ SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
+ SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
+ sfc->regbase + SFC_ICLR);
+
+ /* Enable transfer complete interrupt */
+ reg = readl_relaxed(sfc->regbase + SFC_IMR);
+ reg &= ~SFC_IMR_TRAN_FINISH;
+ writel_relaxed(reg, sfc->regbase + SFC_IMR);
+
+ rockchip_sfc_setup_transfer(nor, from_to, len, op_type);
+ writel_relaxed(dma_buf, sfc->regbase + SFC_DMA_ADDR);
+
+ /*
+ * Start dma but note that the sfc->dma_buffer is derived from
+ * dmam_alloc_coherent so we don't actually need any sync operations
+ * for coherent dma memory.
+ */
+ writel_relaxed(0x1, sfc->regbase + SFC_DMA_TRIGGER);
+
+ /* Wait for the interrupt. */
+ if (!wait_for_completion_timeout(&sfc->cp, msecs_to_jiffies(2000))) {
+ dev_err(sfc->dev, "DMA wait for transfer finish timeout\n");
+ err = -ETIMEDOUT;
+ }
+
+ /* Disable transfer finish interrupt */
+ reg = readl_relaxed(sfc->regbase + SFC_IMR);
+ reg |= SFC_IMR_TRAN_FINISH;
+ writel_relaxed(reg, sfc->regbase + SFC_IMR);
+
+ if (err)
+ return err;
+
+ return rockchip_sfc_wait_op_finish(sfc);
+}
+
+static inline int rockchip_sfc_pio_write(struct rockchip_sfc *sfc, u_char *buf,
+ size_t len)
+{
+ u32 dwords, tx_wl, count, i;
+ unsigned long timeout;
+ int ret = 0;
+ u32 *tbuf = (u32 *)buf;
+
+ /*
+ * Align bytes to dwords, although we will write some extra
+ * bytes to fifo but the transfer bytes number in SFC_CMD
+ * register will make sure we just send out the expected
+ * byte numbers and the extra bytes will be clean before
+ * setting up the next transfer. We should always round up
+ * to align to DWORD as the ahb for Rockchip Socs won't
+ * support non-aligned-to-DWORD transfer.
+ */
+ dwords = (len + 3) >> 2;
+
+ while (dwords) {
+ tx_wl = (readl_relaxed(sfc->regbase + SFC_FSR) >>
+ SFC_FSR_TX_WATER_LVL_SHIFT) &
+ SFC_FSR_TX_WATER_LVL_MASK;
+
+ if (tx_wl > 0) {
+ count = min_t(u32, dwords, tx_wl);
+ for (i = 0; i < count; i++) {
+ writel_relaxed(*tbuf++,
+ sfc->regbase + SFC_DATA);
+ dwords--;
+ }
+
+ if (dwords == 0)
+ break;
+ timeout = 0;
+ } else {
+ mdelay(1);
+ if (timeout++ > SFC_MAX_IDLE_RETRY) {
+ ret = -ETIMEDOUT;
+ break;
+ }
+ }
+ }
+
+ if (ret)
+ return ret;
+ else
+ return rockchip_sfc_wait_op_finish(sfc);
+}
+
+static inline int rockchip_sfc_pio_read(struct rockchip_sfc *sfc, u_char *buf,
+ size_t len)
+{
+ u32 dwords, rx_wl, count, i, tmp;
+ unsigned long timeout;
+ int ret = 0;
+ u32 *tbuf = (u32 *)buf;
+ u_char *tbuf2;
+
+ /*
+ * Align bytes to dwords, and get the remained bytes.
+ * We should always round down to DWORD as the ahb for
+ * Rockchip Socs won't support non-aligned-to-DWORD transfer.
+ * So please don't use any APIs that will finally use non-aligned
+ * read, for instance, memcpy_fromio or ioread32_rep etc.
+ */
+ dwords = len >> 2;
+ len = len & 0x3;
+
+ while (dwords) {
+ rx_wl = (readl_relaxed(sfc->regbase + SFC_FSR) >>
+ SFC_FSR_RX_WATER_LVL_SHIFT) &
+ SFC_FSR_RX_WATER_LVL_MASK;
+
+ if (rx_wl > 0) {
+ count = min_t(u32, dwords, rx_wl);
+ for (i = 0; i < count; i++) {
+ *tbuf++ = readl_relaxed(sfc->regbase +
+ SFC_DATA);
+ dwords--;
+ }
+
+ if (dwords == 0)
+ break;
+ timeout = 0;
+ } else {
+ mdelay(1);
+ if (timeout++ > SFC_MAX_IDLE_RETRY) {
+ ret = -ETIMEDOUT;
+ break;
+ }
+ }
+ }
+
+ if (ret)
+ return ret;
+
+ /* Read the remained bytes */
+ timeout = 0;
+ tbuf2 = (u_char *)tbuf;
+ while (len) {
+ rx_wl = (readl_relaxed(sfc->regbase + SFC_FSR) >>
+ SFC_FSR_RX_WATER_LVL_SHIFT) &
+ SFC_FSR_RX_WATER_LVL_MASK;
+ if (rx_wl > 0) {
+ tmp = readl_relaxed(sfc->regbase + SFC_DATA);
+ for (i = 0; i < len; i++)
+ tbuf2[i] = (u8)((tmp >> (i * 8)) & 0xff);
+ goto done;
+ } else {
+ mdelay(1);
+ if (timeout++ > SFC_MAX_IDLE_RETRY) {
+ ret = -ETIMEDOUT;
+ break;
+ }
+ }
+ }
+done:
+ if (ret)
+ return ret;
+ else
+ return rockchip_sfc_wait_op_finish(sfc);
+}
+
+static int rockchip_sfc_pio_transfer(struct spi_nor *nor, loff_t from_to,
+ size_t len, u_char *buf, u8 op_type)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+
+ rockchip_sfc_setup_transfer(nor, from_to, len, op_type);
+
+ if (op_type == SFC_CMD_DIR_WR)
+ return rockchip_sfc_pio_write(sfc, buf, len);
+ else
+ return rockchip_sfc_pio_read(sfc, buf, len);
+}
+
+static ssize_t rockchip_sfc_read(struct spi_nor *nor, loff_t from, size_t len,
+ u_char *read_buf)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ size_t offset;
+ int ret;
+ dma_addr_t dma_addr = 0;
+
+ if (!sfc->use_dma)
+ goto no_dma;
+
+ for (offset = 0; offset < len; offset += SFC_DMA_MAX_LEN) {
+ size_t trans = min_t(size_t, SFC_DMA_MAX_LEN, len - offset);
+
+ dma_addr = dma_map_single(NULL, (void *)read_buf,
+ trans, DMA_FROM_DEVICE);
+ if (dma_mapping_error(sfc->dev, dma_addr))
+ dma_addr = 0;
+
+ /* Fail to map dma, use pre-allocated area instead */
+ ret = rockchip_sfc_dma_transfer(nor, from + offset,
+ dma_addr ? dma_addr :
+ sfc->dma_buffer,
+ trans, SFC_CMD_DIR_RD);
+
+ if (dma_addr) {
+ /* Invalidate the read data from dma_addr */
+ dma_sync_single_for_cpu(sfc->dev, dma_addr,
+ trans, DMA_FROM_DEVICE);
+ dma_unmap_single(NULL, dma_addr,
+ trans, DMA_FROM_DEVICE);
+ }
+
+ if (ret) {
+ dev_warn(nor->dev, "DMA read timeout\n");
+ return ret;
+ }
+ if (!dma_addr)
+ memcpy(read_buf + offset, sfc->buffer, trans);
+ }
+
+ return len;
+
+no_dma:
+ ret = rockchip_sfc_pio_transfer(nor, from, len,
+ read_buf, SFC_CMD_DIR_RD);
+ if (ret) {
+ dev_warn(nor->dev, "PIO read timeout\n");
+ return ret;
+ }
+ return len;
+}
+
+static ssize_t rockchip_sfc_write(struct spi_nor *nor, loff_t to,
+ size_t len, const u_char *write_buf)
+{
+ struct rockchip_sfc_chip_priv *priv = nor->priv;
+ struct rockchip_sfc *sfc = priv->sfc;
+ size_t offset;
+ int ret;
+ dma_addr_t dma_addr = 0;
+
+ if (!sfc->use_dma)
+ goto no_dma;
+
+ for (offset = 0; offset < len; offset += SFC_DMA_MAX_LEN) {
+ size_t trans = min_t(size_t, SFC_DMA_MAX_LEN, len - offset);
+
+ dma_addr = dma_map_single(NULL, (void *)write_buf,
+ trans, DMA_TO_DEVICE);
+ if (dma_mapping_error(sfc->dev, dma_addr)) {
+ dma_addr = 0;
+ memcpy(sfc->buffer, write_buf + offset, trans);
+ } else {
+ /* Flush the write data to dma memory */
+ dma_sync_single_for_device(sfc->dev, dma_addr,
+ trans, DMA_TO_DEVICE);
+ }
+
+ /* Fail to map dma, use pre-allocated area instead */
+ ret = rockchip_sfc_dma_transfer(nor, to + offset,
+ dma_addr ? dma_addr :
+ sfc->dma_buffer,
+ trans, SFC_CMD_DIR_WR);
+ if (dma_addr)
+ dma_unmap_single(NULL, dma_addr,
+ trans, DMA_TO_DEVICE);
+ if (ret) {
+ dev_warn(nor->dev, "DMA write timeout\n");
+ return ret;
+ }
+ }
+
+ return len;
+no_dma:
+ ret = rockchip_sfc_pio_transfer(nor, to, len,
+ (u_char *)write_buf, SFC_CMD_DIR_WR);
+ if (ret) {
+ dev_warn(nor->dev, "PIO write timeout\n");
+ return ret;
+ }
+ return len;
+}
+
+/**
+ * Get spi flash device information and register it as a mtd device.
+ */
+static int rockchip_sfc_register(struct device_node *np,
+ struct rockchip_sfc *sfc)
+{
+ struct device *dev = sfc->dev;
+ struct mtd_info *mtd;
+ int ret;
+
+ sfc->flash[sfc->num_chip].nor.dev = dev;
+ spi_nor_set_flash_node(&(sfc->flash[sfc->num_chip].nor), np);
+
+ ret = of_property_read_u8(np, "reg", &sfc->flash[sfc->num_chip].cs);
+ if (ret) {
+ dev_err(dev, "No reg property for %s\n",
+ np->full_name);
+ return ret;
+ }
+
+ ret = of_property_read_u32(np, "spi-max-frequency",
+ &sfc->flash[sfc->num_chip].clk_rate);
+ if (ret) {
+ dev_err(dev, "No spi-max-frequency property for %s\n",
+ np->full_name);
+ return ret;
+ }
+
+ sfc->flash[sfc->num_chip].sfc = sfc;
+ sfc->flash[sfc->num_chip].nor.priv = &(sfc->flash[sfc->num_chip]);
+
+ sfc->flash[sfc->num_chip].nor.prepare = rockchip_sfc_prep;
+ sfc->flash[sfc->num_chip].nor.unprepare = rockchip_sfc_unprep;
+ sfc->flash[sfc->num_chip].nor.read_reg = rockchip_sfc_read_reg;
+ sfc->flash[sfc->num_chip].nor.write_reg = rockchip_sfc_write_reg;
+ sfc->flash[sfc->num_chip].nor.read = rockchip_sfc_read;
+ sfc->flash[sfc->num_chip].nor.write = rockchip_sfc_write;
+ sfc->flash[sfc->num_chip].nor.erase = NULL;
+ ret = spi_nor_scan(&(sfc->flash[sfc->num_chip].nor),
+ NULL, SPI_NOR_QUAD);
+ if (ret)
+ return ret;
+
+ mtd = &(sfc->flash[sfc->num_chip].nor.mtd);
+ mtd->name = np->name;
+ ret = mtd_device_register(mtd, NULL, 0);
+ if (ret)
+ return ret;
+
+ sfc->num_chip++;
+ return 0;
+}
+
+static void rockchip_sfc_unregister_all(struct rockchip_sfc *sfc)
+{
+ int i;
+
+ for (i = 0; i < sfc->num_chip; i++)
+ mtd_device_unregister(&(sfc->flash[sfc->num_chip].nor.mtd));
+}
+
+static int rockchip_sfc_register_all(struct rockchip_sfc *sfc)
+{
+ struct device *dev = sfc->dev;
+ struct device_node *np;
+ int ret;
+
+ for_each_available_child_of_node(dev->of_node, np) {
+ ret = rockchip_sfc_register(np, sfc);
+ if (ret)
+ goto fail;
+
+ if (sfc->num_chip == SFC_MAX_CHIPSELECT_NUM) {
+ dev_warn(dev, "Exceeds the max cs limitation\n");
+ break;
+ }
+ }
+
+ return 0;
+
+fail:
+ dev_err(dev, "Failed to register all chips\n");
+ /* Unregister all the _registered_ nor flash */
+ rockchip_sfc_unregister_all(sfc);
+ return ret;
+}
+
+static irqreturn_t rockchip_sfc_irq_handler(int irq, void *dev_id)
+{
+ struct rockchip_sfc *sfc = dev_id;
+ u32 reg;
+
+ reg = readl_relaxed(sfc->regbase + SFC_RISR);
+ dev_dbg(sfc->dev, "Get irq: 0x%x\n", reg);
+
+ /* Clear interrupt */
+ writel_relaxed(reg, sfc->regbase + SFC_ICLR);
+
+ if (reg & SFC_RISR_TRAN_FINISH)
+ complete(&sfc->cp);
+
+ return IRQ_HANDLED;
+}
+
+static int rockchip_sfc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct rockchip_sfc *sfc;
+ int ret;
+
+ sfc = devm_kzalloc(dev, sizeof(*sfc), GFP_KERNEL);
+ if (!sfc)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, sfc);
+ sfc->dev = dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sfc->regbase = devm_ioremap_resource(dev, res);
+ if (IS_ERR(sfc->regbase))
+ return PTR_ERR(sfc->regbase);
+
+ sfc->clk = devm_clk_get(&pdev->dev, "sfc");
+ if (IS_ERR(sfc->clk)) {
+ dev_err(&pdev->dev, "Failed to get sfc interface clk\n");
+ return PTR_ERR(sfc->clk);
+ }
+
+ sfc->hclk = devm_clk_get(&pdev->dev, "hsfc");
+ if (IS_ERR(sfc->hclk)) {
+ dev_err(&pdev->dev, "Failed to get sfc ahp clk\n");
+ return PTR_ERR(sfc->hclk);
+ }
+
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+ if (ret) {
+ dev_warn(dev, "Unable to set dma mask\n");
+ return ret;
+ }
+
+ sfc->buffer = dmam_alloc_coherent(dev, SFC_DMA_MAX_LEN,
+ &sfc->dma_buffer, GFP_KERNEL);
+ if (!sfc->buffer)
+ return -ENOMEM;
+
+ mutex_init(&sfc->lock);
+
+ ret = clk_prepare_enable(sfc->hclk);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to enable hclk\n");
+ goto err_hclk;
+ }
+
+ ret = clk_prepare_enable(sfc->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to enable clk\n");
+ goto err_clk;
+ }
+
+ sfc->use_dma = !of_property_read_bool(sfc->dev->of_node,
+ "rockchip,sfc-no-dma");
+
+ sfc->negative_edge = of_device_is_compatible(sfc->dev->of_node,
+ "rockchip,rk1108-sfc");
+ /* Find the irq */
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get the irq\n");
+ goto err_irq;
+ }
+
+ ret = devm_request_irq(dev, ret, rockchip_sfc_irq_handler,
+ 0, pdev->name, sfc);
+ if (ret) {
+ dev_err(dev, "Failed to request irq\n");
+ goto err_irq;
+ }
+
+ sfc->num_chip = 0;
+ ret = rockchip_sfc_init(sfc);
+ if (ret)
+ goto err_irq;
+#if 1
+ pm_runtime_get_noresume(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
+ pm_runtime_use_autosuspend(&pdev->dev);
+#endif
+ ret = rockchip_sfc_register_all(sfc);
+ if (ret)
+ goto err_register;
+
+ clk_disable_unprepare(sfc->clk);
+ pm_runtime_put_autosuspend(&pdev->dev);
+ return 0;
+
+err_register:
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+ pm_runtime_put_noidle(&pdev->dev);
+err_irq:
+ clk_disable_unprepare(sfc->clk);
+err_clk:
+ clk_disable_unprepare(sfc->hclk);
+err_hclk:
+ mutex_destroy(&sfc->lock);
+ return ret;
+}
+
+static int rockchip_sfc_remove(struct platform_device *pdev)
+{
+ struct rockchip_sfc *sfc = platform_get_drvdata(pdev);
+
+ pm_runtime_get_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_put_noidle(&pdev->dev);
+
+ rockchip_sfc_unregister_all(sfc);
+ mutex_destroy(&sfc->lock);
+ clk_disable_unprepare(sfc->clk);
+ clk_disable_unprepare(sfc->hclk);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+int rockchip_sfc_runtime_suspend(struct device *dev)
+{
+ struct rockchip_sfc *sfc = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(sfc->hclk);
+ return 0;
+}
+
+int rockchip_sfc_runtime_resume(struct device *dev)
+{
+ struct rockchip_sfc *sfc = dev_get_drvdata(dev);
+
+ clk_prepare_enable(sfc->hclk);
+ return 0;
+}
+#endif /* CONFIG_PM */
+
+static const struct of_device_id rockchip_sfc_dt_ids[] = {
+ { .compatible = "rockchip,sfc"},
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rockchip_sfc_dt_ids);
+
+static const struct dev_pm_ops rockchip_sfc_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(rockchip_sfc_runtime_suspend,
+ rockchip_sfc_runtime_resume, NULL)
+};
+
+static struct platform_driver rockchip_sfc_driver = {
+ .driver = {
+ .name = "rockchip-sfc",
+ .of_match_table = rockchip_sfc_dt_ids,
+ .pm = &rockchip_sfc_dev_pm_ops,
+ },
+ .probe = rockchip_sfc_probe,
+ .remove = rockchip_sfc_remove,
+};
+module_platform_driver(rockchip_sfc_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Rockchip Serial Flash Controller Driver");
+MODULE_AUTHOR("Shawn Lin");
--
1.9.1
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